<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<h2>Hello Spring MVC</h2>
<form action="${pageContext.request.contextPath}/user/verifyCode">
    <input name="username" type="text"><br>
    <input name="password" type="text"><br>
    <img id="verifyId" src="${pageContext.request.contextPath}/first/verifyCode" width="220" height="60">
    <a href="javascript:;"
       onclick="document.getElementById('verifyId').src='${pageContext.request.contextPath}/first/verifyCode?'+(new Date()).getTime()">
        换一张
    </a>
    <button type="submit" value="sub">提交</button>
</form>
</body>
</html>